Livestreaming on macbook air lags and high CPU usage

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I am very new to livestreaming.
Recently when trying to go live on YouTube using OBS, I experienced some lagging while streaming. The livestream was saved on a YouTube playlist afterwards, and when viewing it I experienced much more lagging (frame freeze for several minutes) than what I was experiencing while streaming.

I have my suspicion that it might be my machine that causes the problem, bc while streaming CPU usage got high (>50%).

These are the specs:
Machine: MacBook Air, Retina, 13-inch, 2020
Processor: 1,6 GHz Quad-Core Intel Core i5
Memory: 8 GB 3733 MHz LPDDR4X
Graphics: Intel Iris Plus Graphics 1536 MB

My OBS setup included three different scenes, which I would shift between:
Scene 1: Including a WhatsApp videocall and using my laptops camera
Scene 2: Including a local video (source: Media Source)
Scene 3: Including a YouTube video (source: Browser )

I suspect that the combination of this setup and the machines specs might have cause the lagging.
But I am not strong on hardware and what is needed to do such a livestream.

I would like to get some help and understanding to why I am experiencing this issue.
Hope someone can help me.

Note: Sadly, I cannot provide a log file but I hope that the information provided will be 'enough'.

 

[Lawrence_SoCal]

My expertise is not MacOS, so following input is worth less than $0.02, but for what it is worth

real-time video encoding is VERY computationally demanding. then, you are using a laptop, optimized for battery life, which can be thermally constrained (ie reduce compute power when it gets hot)
Now, with that said, with reasonable expectations and settings, your computer should be adequate... but to check we'd need your OBS log
Also, and OBS log does not show what else is going on the computer. Sorry, most Mac Users I know have LOTS of processes (apps, etc) running in the background, and you have a CPU and RAM constrained system. The GPU should be fine for 1080p 30fps video
So, presuming you'd rather spend your time than money, I'd recommend becoming familiar with your native operating system (OS) monitoring tools (System Monitor?), and learn what it means to optimize your OS (stopping/turning off apps that don't need to be running, adjusting eye-candy and similar settings to reduce CPU/GPU/RAM/disk I/O demands on system). Do NOT have lots of unused browser tabs open (using monitoring tool to see RAM impact, hence the recommendation)
A CPU at 50% consistently is busy, but ok.... *IF* the system isn't thermal throttling, in which case you may actually be at 100% (and that would cause lots of problems)

Hope that helps until a more knowledgeable MacOS user responds